The purpose of this project is to evaluate treatment information for female breast cancer and prostate cancers. The research will focus on improving the completeness, quality and use of first course of treatment and stage data, and on describing patterns of care for these two cancers. This will be a collaborative effort among six state registries and the Centers for Disease Control, and is part of a larger effort to use data from the National Program of Cancer Registries (NPCR) to perform enhanced surveillance and operational research on several cancers. The project has four specific objectives: 1) Determine the proportion of patients who received the recognized standard of care for stages I through III female breast cancer; 2) Describe the treatment patterns for all stages of prostate cancer; 3) Determine the tumor, patient, provider, and health system characteristics that are associated with different cancer treatments for female breast and prostate cancers; and 4) Assess the completeness and quality of the stage and first course of treatment data that are collected by cancer registries for female breast and prostate cancers. We propose to use staff from the Los Angeles Cancer Surveillance Program (LA-CSP) and from the Desert Sierra Cancer Surveillance Program (DS-CSP) of the California Cancer Registry (CCR) to collect staging and treatment information from hospital and physician medical records for 2,000 breast and 2,000 prostate cancer patients diagnosed in the two most recent years (2004, 2005) in Southern California. Data collection methods will be developed collaboratively with other investigators using experience obtained during prior patterns of care studies. The effect of patient socieoeconomic status, urban rural residence, comorbid illness and insurance type on treatment will be evaluated as well as provider (physician and hospital) characteristics. The results of this research may be used both to evaluate patterns of care for two priority cancers, and to evaluate treatment information in population based registries. What is learned about treatment quality and completeness can subsequently be used to improve the information in these registries so that they can become a resource for researchers evaluating quality of cancer care. [unreadable] [unreadable] [unreadable]